Systems and methods for minimizing scattered light in multi-SLM maskless lithography

Abstract

The present invention is directed to a lithography system in which scattered light from a pattern generator, having one or more pattern generating devices, is blocked from an object, such as a wafer or display. The system includes a pattern generator with multiple pattern generating devices, a projection system for directing light from the pattern generating device, and an aperture located at or near an object window. The aperture has a profile that matches the configuration of the pattern generating devices. A method for blocking scattered light in a lithography system using multiple pattern generating devices is also provided.

1. A system, comprising:
 a plurality of patterning devices, each patterning device comprising a reflecting portion, the reflecting portion including an array of programmable elements that each are configured to produce a beam, and a non-reflecting portion, wherein respective beams form a patterned beam and wherein the non-reflecting portion is configured to produce stray beams; 
 a projection system configured to direct the patterned beams onto a surface; and 
 an aperture device comprising a number of openings, the number corresponding to a number of the patterning devices, the openings arranged in a configuration to correspond to locations of the patterning devices, the openings being arranged in a configuration to transmit the patterned beam, while substantially blocking the stray beams; 
 wherein a spacing between adjacent ones of the elements in each of the array of programmable elements is smaller than a spacing between adjacent ones of the patterning devices. 
 
   
   
     2. The system of  claim 1 , wherein the patterning devices are spatial light modulators. 
   
   
     3. The system of  claim 2 , wherein said spatial light modulators are digital micromirror devices. 
   
   
     4. The system of  claim 2 , wherein said spatial light modulators are transmissive liquid crystal light valves. 
   
   
     5. The system of  claim 2 , wherein said spatial light modulators are grating light valves. 
   
   
     6. The system of  claim 1 , wherein said aperture device is an aperture plate. 
   
   
     7. The system of  claim 1 , wherein said aperture device is etched onto a window near an object plane of the projection system. 
   
   
     8. The system of  claim 1 , wherein said aperture device is etched onto a window near an image plane of the projection system. 
   
   
     9. The system of  claim 1 , wherein said aperture device is etched onto a lens within the projection system. 
   
   
     10. The system of  claim 1 , wherein the non-reflecting portions scatter incident light.